They also said the law would have been problematic for agricultural vehicles.

"It's difficult when you have ag vehicles. You can't always maintain a highway speed under those circumstances," White said.

White said Colorado's frequent inclement driving conditions - and numerous tourists on the state roads who are unfamiliar with such conditions - also made the bill problematic.

"There is no such thing as a speed limit on hazardous roads. That's kind of a nebulous situation," White said. "I get just as frustrated as anyone, but the larger issue is safety. : I think what's unsafe about it is expecting anybody who's unfamiliar with mountain driving conditions to drive at a speed that other people are comfortable with."

The state House of Representatives previously had passed the bill Jan. 26 in a 37-27 vote. The bill, sponsored by Rep. Michael Merrifield, D-Manitou Springs, would amend state law to require any slow-moving vehicle on a state highway with a line of five or more vehicles behind it to pull over at the first safe opportunity. The minimum speed regulation section of the Colorado Revised Statutes already forbids driving so slowly that it impedes traffic, but supporters of House Bill 1042 said the legislation would provide a standard to determine when a driver deserves a ticket. County sheriffs of Colorado supported the law.

"I am not familiar with the bill, but I am familiar with the concept," Routt County Sheriff Gary Wall said. "I think the concept is good. I have been faced with that situation a lot, like most people have, and I think, 'Gosh, why doesn't that person pull over?'"

Wall said the frustration of such situations leads to problems.

"It really does create a safety situation because people do things they wouldn't normally do," he said.